Procedures for the three-dimensional (3-D) dynamic analysis of earth dams have been available for over 25 years. However, additional case histories are needed to assess whether such procedures are capable of simulating the seismic response of dams in narrow canyons, and to further evaluate the effects of 3-D behavior on the response of such dams. This paper describes a study aimed at identifying the vibration characteristics of Seven Oaks Dam during the 2005 Yucaipa and 2001 Big Bear Lake earthquakes, and at evaluating the applicability of 3-D and two-dimensional numerical procedures to simulate the recorded response of the dam.